Image forming apparatus employing cleanerless system

Abstract

An image forming apparatus includes a developing roller and a photosensitive drum configured to rotate about a first axis, and has a peripheral surface. The developing roller is configured to contact the photosensitive drum and is configured to supply developer to the photosensitive drum by rotating about a second axis positioned lower than the first axis in a vertical direction to form a visible image on the peripheral surface. Extraneous matter on the peripheral surface is recovered only by the developing roller.

What is claimed is: 
     
       1. An image forming apparatus comprising:
 a photosensitive drum configured to rotate about a first axis and having a peripheral surface; 
 a developing roller configured to contact the photosensitive drum and configured to supply developer to the photosensitive drum by rotating about a second axis positioned lower than the first axis in a vertical direction to form a visible image on the peripheral surface, extraneous matter on the peripheral surface being recovered only by the developing roller; and 
 a film member overlapping the first axis when projected in the vertical direction and having a portion contacting a circumferential surface of the developing roller. 
 
     
     
       2. The image forming apparatus according to  claim 1 , further comprising a transfer roller configured to contact the photosensitive drum and configured to rotate about a third axis positioned lower than the first axis in the vertical direction, the transfer roller configured to transfer the visible image from the peripheral surface to a recording medium, only the developing roller and the transfer roller being in contact with the photosensitive drum. 
     
     
       3. The image forming apparatus according to  claim 2 , wherein the photosensitive drum and the transfer roller define a contact portion therebetween, the photosensitive drum being rotatable in a rotating direction such that the recording medium passes through the contact portion; and
 wherein the contact portion has an upstream end portion in the rotating direction positioned lower than the first axis in the vertical direction. 
 
     
     
       4. The image forming apparatus according to  claim 3 , wherein the contact portion in its entirety is positioned lower than the first axis in the vertical direction. 
     
     
       5. The image forming apparatus according to  claim 2 , further comprising a charger configured to charge the peripheral surface and positioned higher than the first axis in the vertical direction to confront but remain separated from the photosensitive drum. 
     
     
       6. The image forming apparatus according to  claim 5 , wherein the photosensitive drum and the transfer roller define a contact portion therebetween, the photosensitive drum being rotatable in a rotating direction such that the recording medium passes through the contact portion;
 wherein the image forming apparatus further comprises an exposing device configured to emit a laser beam to the photosensitive drum to form an electrostatic latent image on the peripheral surface; 
 wherein the recording medium that has passed through the contact portion is discharged between the charger and the transfer roller in a peripheral direction of the photosensitive drum; and 
 wherein the laser beam passes between the charger and the developing roller in the peripheral direction of the photosensitive drum. 
 
     
     
       7. The image forming apparatus according to  claim 1 , further comprising a supply roller configured to supply developer to the developing roller, the supply roller being positioned opposite to the photosensitive drum with respect to the developing roller. 
     
     
       8. An image forming apparatus comprising:
 a photosensitive drum configured to rotate about a first axis and having a peripheral surface; 
 a developing roller configured to contact the photosensitive drum and configured to rotate about a second axis positioned lower than the first axis in a vertical direction; and 
 a transfer roller configured to contact the photosensitive drum and configured to rotate about a third axis, the transfer roller being positioned higher than the second axis in the vertical direction, only the developing roller and the transfer roller being in contact with peripheral surface. 
 
     
     
       9. The image forming apparatus according to  claim 8 , wherein the third axis is positioned lower than the first axis in the vertical direction. 
     
     
       10. The image forming apparatus according to  claim 8 ,
 wherein the third axis is positioned lower than the first axis in the vertical direction; and 
 wherein the transfer roller is configured to transfer a visible image from the peripheral surface to a recording medium. 
 
     
     
       11. The image forming apparatus according to  claim 8 , further comprising a charger configured to charge the peripheral surface and positioned higher than the first axis in the vertical direction to confront but remain separated from the photosensitive drum. 
     
     
       12. The image forming apparatus according to  claim 11 , wherein the photosensitive drum and the transfer roller define a contact portion therebetween, the photosensitive drum being rotatable in a rotating direction such that a recording medium passes through the contact portion;
 wherein the image forming apparatus further comprises an exposing device configured to emit a laser beam to the photosensitive drum to form an electrostatic latent image on the peripheral surface; 
 wherein the recording medium that has passed through the contact portion is discharged between the charger and the transfer roller in a peripheral direction of the photosensitive drum; and 
 wherein the laser beam passes between the charger and the developing roller in the peripheral direction of the photosensitive drum. 
 
     
     
       13. The image forming apparatus according to  claim 8 , further comprising a film member overlapping the first axis when projected in the vertical direction and having a portion contacting a circumferential surface of the developing roller.